


Race Against Time

by ghostings



Category: Big Hero 6 (2014)
Genre: AU, Big Hero 6 - Freeform, Feels, Fluff and Angst, Fluff and Hurt/Comfort, Gen, Hurt/Comfort, Light Swearing, Lung Cancer, bh6 - Freeform, cancer au, hidashi
Language: English
Status: In-Progress
Published: 2015-02-15
Updated: 2016-08-29
Packaged: 2018-03-09 04:31:10
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 10
Words: 19,715
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3236291
Author URL: https://archiveofourown.org/users/ghostings/pseuds/ghostings
Summary: <blockquote class="userstuff">
              <p>At ages 2 and 6 Hiro and Tadashi Hamada were known as two of the most intelligent children in all of San Fransokyo. At ages 3 and 7 they became orphans, and Cassandra Hamada became a single woman trying to raise her two nephews. At age 10 Hiro was diagnosed with lung cancer due to the heavy exhaust and smoke inhalation from the car crash that killed their parents. The Hamadas were dealt a horrible hand of cards in the poker match of life, but they weren’t once to fold - they would simply make do.</p>
            </blockquote>





	1. Sore Losers

**Author's Note:**

> This is my first Big Hero 6 fanfiction I'm posting here, and I'm pretty excited. This is a cancer au my friend helped me work out a bit. It's not fully thought-out, so I apologize for any gaps/mishaps because of course, I'm not a doctor so it takes a while to make sure what I'm writing actually applies to human beings hah. I hope you like it, and please let me know what you think!

**Summary for the Chapter:**

> Right now, Tadashi was working on his newest project, trying and hoping that it would work this time… It had to work! All of his other experiments had worked - this one could be no different, his brother’s life depended on it. If the doctors couldn’t do anything with today’s technology, Tadashi would make advanced technology that could.

Hiro groaned in frustration as he spun around in his computer chair, bored out of his mind and not having a single idea of anything to work on. He didn’t have the right parts he needed to finish his Megabot and he needed a new lens before he could test out his camera dragonfly again. He wanted to work on something new today, but his brain was completely empty. 

The teen gave a few coughs into his hand, wincing with a rub to his throat. Today felt like it was going to be one of  _those_  days - not exactly bad, but not exactly good, either. He just hoped Tadashi got home from school soon. Maybe they could play some video games together?   


Tadashi was always quiet when he was by himself; he fed off of the energy around him, able to get along with almost anyone. However, many people were confused by him. Despite his popularity and power on the campus, he never used it, and he never really went anywhere besides home and the university. If anyone saw him anywhere else, he was always with his brother. He never went out or to parties (not that people hadn‘t tried to get him to). He just worked and then went home.

No one understood it and not even his friends dared to ask about it, knowing from the past how defensive he got whenever they would try to ease into it.

Right now, Tadashi was working on his newest project, trying and hoping that it would work this time… It _had_ to work! All of his other experiments had worked - this one could be no different, his brother’s life depended on it. If the doctors couldn’t do anything with today’s technology, Tadashi would make advanced technology that could.

Hiro worried about his big brother a lot. Tadashi seemed like he didn’t do much, like he was secluding himself from other people that he could be interacting with. Hiro knew he had friends, he’s heard him talk about them before, but he didn’t seem to do much with them outside of the nerd lab and nerd school. Even though he might not have a very long life, Hiro didn’t want his elder brother wasting his worrying about him. He wanted him to go out and have a good time with people. At least having those relationships with other people would make the pain easier if worst comes to worst - he hoped.

The doctors said he might not make it to be eighteen. If he fought hard enough, he might be able to get up to twenty-five, but they didn’t see much hope in that. Hiro was already thirteen, it’s been three years since his first diagnosis and he’d heard the doctors’ whisper about how he was ‘ _too small’_ and ‘ _too weak’_.

He didn’t believe it though, no one in the family did; the Hamadas were fighters, there was no room for giving up.

 _“I’m not giving up on you…”_ Tadashi whispered. He wasn’t sure if he was talking about Hiro or his robot. He reached up to turn Baymax on but stopped as the alarm on his watch went off and he quickly moved to get his things together.

It was time to go home.

He could really stay as long as he wanted, and though it was tempting at times, he never did. He wanted to spend as much time as he could with Hiro, just in case he did fail…

It only took a few minutes for him to get home and upstairs, smiling as he noticed a bored Hiro. “Hey.” He greeted happily, taking his satchel and jacket off. His smile widened when he saw his brother perk up and grin when he came in.

"Tadashi!" He greeted happily, getting up from his chair to go hug his brother. Tadashi smiled and returned the hug. He loved coming home when Hiro wasn’t busy; he would always greet Tadashi with a hug, which was way better then the usual ‘hey’ he’d mumble in response.

 "How was school? Did you work more on that _super secret_ project?" Hiro had heard Aunt Cass talking about it ones and he was very interested in finding out what it was.

 “School was the same, lectures and reviews.” Tadashi answered before smiling lightly. “Yes I did, we were allowed free-lab today…” He said lightly. “I can’t _wait_ to show you my invention once I’m done.”

After all, Tadashi’s hope was that Baymax could cure Hiro’s lung cancer. He wanted his brother to live - he knew Hiro was strong, and he was going to do anything he could to prove the doctors wrong; that he _wasn’t_ too small or too weak; he would survive.

 That was wishful thinking though, something Hamada’s were known for, aiming high and doing everything they can to reach their goal. However, Tadashi had learned that when it came to their family, no one was lucky and happiness wasn’t meant to last.

“What about you, what did you do today?” Tadashi asked curiously before Hiro began to cough roughly, and he pulled away to give the boy room to breathe, knowing it’d pass.

The pain that shot through Hiro’s chest was better than what it could have been, but he still scrunched his face and rubbed down the middle of his chest softly, as if what was hurting him could disappear with a little pressure. He gave a small, tired smile to his brother nonetheless.

“Haven’t done much today beside trying to come up with new ideas. Got nothing though,” he shrugged.

 “Washed out at fourteen? So sad.” Tadashi said playfully, accepting the smile happily. He worried about his brother, but he knew Hiro didn’t like to be coddled.

"I can’t wait to see what you're working on, Nii-San," Hiro said after a minute. "I bet it’s going to be the best yet."

Tadashi just sighed lightly. “I sure hope so…” That was the plan, at least. “Well then, what would you like to do with the rest of today, Hiro?”

"Um…" he tried to think about what he wanted to do, but simply shrugged. "We could always play some video games? I wouldn’t mind beating you in Mario Kart again."

“What makes you think you can beat me?” His brother questioned playfully. “Maybe I won’t go easy on you this time and I’ll beat you instead.”

"Oh, you are _so_ on!" Hiro chuckled and ran down the stairs, "Come on slow poke! Time to get your butt kicked!"

Tadashi laughed. “I’m coming!” He called back, taking two steps at a time and quickly setting the game up before sitting down next to Hiro. “Ready to lose to your older brother?” He asked playfully.

"You wish," Hiro laughed before they picked their characters the games begun. 

It was three straight hours of tournament style racing and the teen frowned deeply as he dropped his controller and glared over at his brother. Tadashi’s character was jumping up and down on the screen with the trophy, while Hiro’s stood sadly off to the side with a second place metal around its neck. 

"You suck," he told him simply. 

Tadashi laughed lightly. “Aw, are you being a sore loser?” He questioned, setting the controller down. This was fun, he liked doing fun things with Hiro, but Hiro did have a tendency to hate losing so Tadashi would throw the game sometimes, last time was one of those times. Because he _so_ didn’t notice the bananas on Mushroom Gorge‘s giant mushrooms.

“Want to go another round?”

Hiro grinned, “Of course.” He loved playing games with Tadashi, spending time with him and being able to act like any normal teenager. It was fun, helping keep him distracted from the tumor eating his lungs and making the fear just a little easier to bear. Being around Tadashi had an effect like that. He could always make you forget anything you were worried about, and make you feel twenty times better than any medication ever could.

He went to pick up the control when pain tore through his chest and he gasped, shaking fingers clutching tightly at his shirt as he leaned forward, eyes squeezed shut.

He couldn’t breath, fire running through his ribs until he could force a cough and gasp in air, tears dripping down his face as the pain slowly started to ebb into a full throb and he could take shallow breathes.

 “No, no, Hiro, calm down and relax - deep breaths.” Tadashi instructed, pulling Hiro’s hand away and sitting him up straight. He made sure his shirt wasn’t too tight to block his airway, before he got up and ran to the bathroom, to get the air tank that the doctors had given them.

Hiro whimpered, pain shooting through his chest again as he did so. Oh he wanted nothing more than just to pass out so he wouldn’t have to feel this.

Tadashi rushed back out, plugging it in and putting the mask to Hiro’s mouth and nose. Hiro was grateful and put his hand over the mask to keep it in place as he closed his eyes and took deep breaths.

Tadashi was ready to call the hospital, even if he was reluctant due to his brother’s fear.

“I…I’m calling your doctor Hiro.” Maybe he’ll do a home visit or tell them what more to do.

"O-okay…" Hiro said breathlessly, just trying to focus on catching his breath and getting the ringing in his ears to stop.

As soon as the beginning of Hiro’s confirmation was out, Tadashi was quickly calling the doctor, explaining what happened quickly when the older man answered. He thanked the doctor quickly before hanging up and going back to Hiro, holding the mask for him. “He’ll be here with the nurse in five minutes…”

"Kay…" Hiro murmured, closing his eyes as he leaned his head back. He was suddenly so tired, like all his energy had been zapped out. It was per-usual with episodes. He was just grateful this was a smaller one. 

When the doctor and nurse came, the doctor took Tadashi’s place, kneeling in front of Hiro and removing the mask to get the boy to open his mouth wide. Hiro did so and the doctor checked both his throat and his breathing, giving him a scan with a small portable device, before giving him a treatment, which consisted of an injection of medication and a spray that he had to breath in three spritzes from. 

Tadashi watched carefully as the younger was taken care of, taking mental note of everything that was happening. This could be useful for programming Baymax, after all.

"He’ll be alright," the doctor reassured Tadashi as he stood and the nurse was talking with Hiro. He looked down at the scanner in his hand that showed an x-ray of Hiro’s chest and lungs, black spots in the lungs showing where the tumor was. "It looks like the treatment is doing its job. No spreading of the tumor, just some irritation to the sensitive areas around it. I recommend he rests for the rest of the day and sleeps with the mask on tonight, propped up, to make sure there isn’t any restriction to his airways."

“I’ll make sure he’s taken care of.” Tadashi promised before sighing as the nurse packed their things again. He was thankful for the small blessing of the tumor not spreading… That’d give Hiro some time…

“Thank you for coming.” He said, closing the door behind them. Not a second later did Cass come up.

“Hey what happened? I thought I heard Hiro’s doctor.” She asked, still wearing her apron before looking to Hiro then back to Tadashi. “Is everything alright?”

“Yeah… Hiro just had a small attack, so I called him. He said that Hiro will need to rest and sleep with his mask, propped up on pillows.” Tadashi explained, catching Cass up to speed.

“What?-Why didn’t you come get me?!” Cass demanded.

Tadashi sighed before lowering his voice. “Because then you’d close the café for the third time this week…” Hiro inwardly winced. He had really hoped she wouldn’t have to know about the attack. He’s had two others earlier in the week and she’d been so stressed out about it, he hated doing that to her. He hated doing that to both of them. 

Cass pressed her lips into a line before her shoulders sagged in defeat. “You’re right.” She responded before turning to Hiro and walking to him with a small smile. “Do you feel better Hiro?”

Her nephew let out a soft sigh and looked up at her tiredly, smiling faintly. “Not really…” he murmured, still a little breathless, but the tank was helping. “‘m sorry for worrying you guys….”

Cass _tsk_ ed lightly. “Don’t be silly, hun. It’s no worries at all.” She assured, kissing his forehead before hearing the café’s bell go off. Cass sighed lightly and stood, she didn’t want to go but she did have a job to keep… Besides Tadashi would take care of Hiro. “I’ll make you something easy to eat tonight.”

Hiro nodded and gave a weak smile under the mask and watched her go down the stairs sluggishly. He hated how much one attack could suddenly bring reality crashing down on them once again. He was going to try harder this time though. He made a mental goal that he wasn’t going to have another attack for a whole week, and maybe his body will get used to that and go longer between them. Maybe, by some miracle, he’ll wake up one day and the cancer will be gone. Wouldn’t that be something?

Tadashi went to Hiro with a smile before picking him up carefully with the tank. This was getting harder to do since Hiro was growing, but Tadashi didn’t mind at all.  
Hiro wrapped his arms slowly around Tadashi’s neck, leaning into his shoulder as they went upstairs.

“I think we’re done with our gaming tournament for today-maybe next time we can play Smash Bros.” Tadashi suggested as he carried Hiro upstairs and carefully laid him in his bed.

 “I’ll win that one, Pikachu is always the best to kick Link’s butt.” he said weakly. He took a deep breath, as deep as he dared, and let it out slowly, rolling his shoulder to try and loosen some of the pain there. He was becoming achey and sluggish, something he really hated with this.

Tadashi chuckled. “Don’t try and make me feel better with stats, I know you’re a natural at fighting games, from Street Fighter and Mortal Combat to Hyrule Warriors.” He said knowingly and moved Hiro’s pillows so that they’d prop him up better. Tadashi was attentive in making sure that it was also still comfortable. He was always like this, wanting to make things the best they could be for Hiro so the younger wouldn’t have to stress in his condition.

Swallowing, Hiro looked up at his brother, “It’s getting harder to carry me, isn’t it? I can always walk, you know.” He gave the suggestion casually, not wanting to seem like he was trying to take that away from Tadashi, but just to let him know that he didn’t have to burden himself with that all the time. 

“No-no, it’s not you Hiro.” Tadashi assured Hiro, finishing and stepping back before going to replug the tank in so it wasn’t running off of its stored energy. He then and sat down on the edge of the bed.  
“The tank seems to be getting heavier.” It was partially the truth, seeing as Hiro got a new tank every year and they seemed to grow in size with Hiro. If it got any heavier…then they might need to have separate rooms so Hiro could stay on the main floor and Tadashi didn’t want that. He didn’t feel safe like that, leaving Hiro in his own room where no one could monitor him.

That was Tadashi’s job, and he was good at it. For some reason he could sense when to wake up to help Hiro even if the tank is loud and Hiro doesn’t say a thing. He just knows.

"Well…who knows. Maybe by next year…I won’t ever need the tank again. Hopefully, this’ll be gone and we won’t have to bother with it ever again." Hiro said optimistically, letting his hand fall back to the bed. 

There _was_ promise of the cancer getting better. The medication was experimental, but there had already been a handful of other successful cases, where the tumor started shrinking and the doctors were either able to remove it, or the chemotherapy killed it. Hiro’s doctor had been optimistic about the outcomes and it seemed like they were working. It didn’t mean he didn’t have good and bad days or the ones in between, but it gave him the energy to push through; fight even harder.  

Tadashi laughed lightly, giving Hiro a real smile.

“Maybe…” He said hopefully and wishfully. He wanted the same thing, for this cancer to dissolve into nothingness, but he knew that it couldn’t happen. It was against science. His only hope was to change it.


	2. That's Rough, Buddy

**Summary for the Chapter:**

> Tadashi turned Baymax on and was pleased as nothing went wrong, no annoying sound, no black out. This was good, but Tadashi wasn’t holding his breath. Something had to go wrong…it always did.

**Notes for the Chapter:**

> This chapter is pretty short, just moving things along. I hope you guys are enjoying, please let me know what you think!

The next week went smoothly. Hiro didn’t have any attacks, only small scares, and Tadashi was able to advance more on Baymax. He was so close - he could feel it…

Tadashi turned Baymax on and was pleased as nothing went wrong, no annoying sound, no black out. This was good, but Tadashi wasn’t holding his breath. Something had to go wrong…it always did.

And it did. 

It was after two in the morning when it happened. Hiro knew something was wrong, he could feel it, and fought to resurface from his dreams to fix the problem. However, when his eyes shot open he realized he couldn’t breath. Pain was coursing through every inch of his body and even with the mask, he couldn’t seem to pull enough air in. One of his lungs felt full, like a weight was pulling on it and air couldn’t get through. 

He leaned forward, coughing and gasping for air. “T-‘ad’shi…!” he cried weakly, panting and clutching at his chest. “Ta-Ta-d'shi! Cass!” Tears were running down his face, mixing with the sudden sweat as he ran a hand through his hair, leaning forward as far as he could and letting his hand drop to clutch at the blanket. He didn’t know what to do; he was terrified.

It hurt. _It hurt.  
_

 

Tadashi smiled as he drove home. Baymax had actually responded - his sensors still weren’t responding and he wasn’t following protocol, but it was already a wonder!

Maybe this was a sign that things were getting better, that they would be okay. That not everything had to be bad.

He made it home late that night. Yes, he was worried to leave Hiro alone, but Hiro hadn’t had an episode in a while, so he assumed that it would be fine. He locked up his Moped and went inside, locking the door behind him.

He was halfway up the stairs before he finally heard Hiro’s cries and immediately dropped his stuff, running up the rest of the stairs to see his brother struggling. “Hiro!” Tadashi exclaimed, rushing to him.

“What‘s going on up here?” Cass asked tiredly before looking to Hiro and immediately waking up. She hurried to his other side. “Are you okay?” Cass asked as she ran her fingers through his hair, already knowing the answer, but wanting to keep Hiro responsive.

Hiro leaned into his aunt, gasping for breath and whimpering in pain, his hand tight in his shirt. “Hurts…hurts….” he sobbed, gasping.

“I’ll get help, just hold on.” Tadashi knew it was too late to call the doctor so that left one option.

“ _911, what’s your emergency?_ ”

What was the point of asking, couldn’t they just send someone!  
Tadashi quickly explained everything and they assured him an ambulance was coming.

When the ambulance came, Hiro had a vice grip on Tadashi’s hand, his vision blurry and his face dripping with tears and sweat. They rushed him to the hospital as soon as they broke Hiro’s grip on Tadashi, and Cass drove Tadashi and herself in the truck after them.

He was rushed to the emergency room and it wasn’t for several hours later that a doctor came to tell them what was wrong.

"Fluid was starting to fill up his lung, preventing oxygenation. We put a tube in through the back of his chest to drain it out, and set him up with a nasal cannula for better air flow. He’ll be out for the rest of the night, but you two are welcome to go stay with him if you want." The doctor said softly.

Cass sighed in relief. However, Tadashi clenched his fist. That wasn’t good enough - it was just a temporary fix.

“Thank you doctor, we’ll stay.” Cass said lightly.

“Not me.” Tadashi said immediately.

Cass looked at him in shock. “What- why? You know Hiro’s going to want to see you when he wakes up.”

“I need to work.” Tadashi said looking to Cass. “I’m so close to getting it right - I just know it.”

Cass looked at him sadly before sighing and hugging him. “I’ll text you if he wakes up before you get back…”

“Thank you…”

Tadashi ended back at the labs with full intent of finishing his project. He turned on the lights and went straight to his computer, turning it on and typing furiously on it. Programming as fast as he possibly could. A temporary fix wasn’t going to cut it-he wanted Hiro completely cured. And it would happen or he would die trying!

He worked for hours on end, even chugging coffee to make himself work faster. Tadashi felt past exhaustion when the sun came up. He paid it no mind and pushed Baymax’s chip back in, watching it slide in before yawning and stretching. Unfortunately, he ended up stubbing his toe on the table’s leg as he did so. “Ow!” He exclaimed cradling his foot. Well, at least that woke him up a bit.

“Hello I am Baymax; you’re personal health care companion.”

Tadashi looked up to the inflated robot in wonder. It worked… He worked!

**Notes for the Chapter:**

> Hope you're liking it, let me know what you think!


	3. Something to Look Forward To

**Summary for the Chapter:**

> Hiro finally has something to look forward to.

The room Hiro was in was covered in soft pastel colors and animal designs. The children’s hospital always liked to keep the rooms fun and colorful to help ease fears of being there. Nurses came in to check up on them regularly, offering to get things for Cass after she had checked on Hiro. The poor boy looked so much smaller in the bed than he usually did, hooked to wires and tubes. It broke Cass’s heart seeing her baby like this. 

Hiro didn’t show any signs of waking until the late morning. He was weak and didn’t want to open his eyes yet, not ready to be assaulted by the light of the room. He let out a soft groan, turning his head slightly towards where he felt pressure on his hand. 

“‘Dashi…?” he croaked softly, not knowing if his brother was there or not. 

Cass was with Hiro when he woke up, explaining to him what happened. Hiro blinked his eyes open just a hair and lifted the side of the hospital shirt to see the tube running up his side, the aching pressure in his lower back where it was still inserted. They’d drained a liter and a half, apparently.

That explained why he’d felt like there had been water in his lungs last night - there _had_ been. 

When the doctor came in to check up on Hiro and examine him, Cass left the room to text Tadashi. 

[Text]: Hiro’s awake and he’s asking for you. Please hurry over here.   
  


“You are in pain… On a scale from one to ten; how would you rate your pain?” Baymax asked as the screen on his chest lit up with faces.

“Zero!” Tadashi ran a hand through his hair, not caring as his hat fell off in the process, and looked close to tears as he left out a small choked laugh. “You work…You work! -Oh my - wait until Hiro sees you!” He exclaimed, hugging the robot.

Baymax blinked. “I am…confused… What are you doing?”

Tadashi gave another laugh. “I’m hugging you.” He said simply before he heard his phone beep. He pulled away and grabbed it off the table.

“Does hugging help?”

“Sometimes…” Tadashi said as he read the message and quickly got his things. “I…I have to go Baymax.”

“Go where? I have not yet helped you.”

“I’m fine.” Tadashi assured and noticed Baymax wasn’t going to go away on his own. What were the deactivating words?  
“I am satisfied with my care.” He said and smiled as Baymax went back to his charging station and deflated. He was excited!

Tadashi made it back to the hospital just as the nurse let Cass back in and entered Hiro’s room with her.

"About time," Cass teased him softly when he finally showed up, bumping her shoulder with his affectionately as they walked into the room. 

“Sorry.” Tadashi apologized to Cass, though he had a bright smile. “I got him to work though.” He whispered to her quietly before looking to Hiro, his smile only falling slightly at the sight of Hiro.

Hiro was pale and still weighed down with the medical equipment, but he was awake and grinning tiredly at the two of them.

“Nii-chan!” he croaked, his voice hoarse, “Hey…”

 “Otouto.” Tadashi greeted back and walked to Hiro, sitting on the edge of the bed away from the equipment as not to mess with any of it. “How do you feel? Any better?” He doubted it but was hopeful.

Hiro shrugged slightly, “I can breathe,” he croaked with a smirk, “So that’s improvement…don’t feel any different though. Really tired…there wasn’t any tumor growth though, so that’s good.”

“ _Very_ good,” Tadashi confirmed and reached out to ruffle Hiro’s hair. “I’m sorry for not being here right when you woke up, but I have a surprise for you when you’re able to get out.” He said soothingly with a confident smile.

"It’s okay. Aunt Cass said you had nerd things to do. I get it."

The teen coughed weakly, pursing his lips and furrowing his brows as it pulled at the tube.

"Ugh. I want this thing out!" he complained in annoyance, moving the gown a bit to glare at the tube in his back. Oh, how he hated the hospital.

 “I know,” He said softly before sighing. Hopefully Hiro would never need to be like this again. Baymax was operational, the only question was if Tadashi had advanced the medical field far enough for Baymax to know what to do.

“I finished my project…and I want you to be the first one to see him.”

Hiro smiled.

“Something to look forward to.”


	4. Are You Satisfied With Your Care?

**Summary for the Chapter:**

> "But I think Baymax is amazing! You did a great job with him, Tadashi. The San Fransokyo Children’s Hospital is having their annual convention. You should totally enter into their robotics contest and see if they’ll put him into the staff! It’d make a lot of kids feel more at ease, especially in the cancer wing."
> 
> “Well I’m glad you like him…because he was built for you.”

**Notes for the Chapter:**

> Here, have a ridiculously long chapter after a bunch of ridiculously short ones!

Tadashi had stayed in the hospital with Hiro, not going to classes because he was afraid something would happen. Aunt Cass could calm Hiro, but Tadashi could do it faster and without babying him too much. Once he was released Tadashi was relieved and happy to see his brother without the many tubes hooked up to him. He didn’t care that Cass and he would have to help Hiro more: he never minded helping his little brother.

Hiro was in the hospital for nearly a week, but even after he was released, he hadn’t gotten too much of his strength back. Attacks like that always took so much out of him, especially when they had given him a low chemo treatment before letting him go, hoping to kill the part of the tumor that had cause his lung to fill.

"It’s because he’s so small," the doctors would say, "The cancer has wrung him so dry it will take time before he’s strong enough to do his everyday tasks again."

He had to rely heavily on Tadashi and Cass’s help, even using a crutch when he walked to ease some of the strength it took. Longer walks called for a wheelchair, which Hiro hated, but couldn’t do much about. All of this angered the boy greatly, and he would have occasional, sudden outbursts that startled and saddened his family. He just hated feeling incapable, and like such a burden: because that's what he was. He wished he would just get better or die already so that Cass and Tadashi wouldn't have to worry about him. Immediately, Hiro pushed the thought away. No, he couldn't die. He couldn't do that to Tadashi. He  _needed_  to get better. 

He slept most of the time, only waking to eat a little and maybe play with his sketchbook if he felt up to it. It was nearly a week since he was released, and Tadashi was getting ready for school quietly in hopes not to wake his brother. But Hiro was awake, and watched his brother for a few minutes before speaking up.

"Nii-San, can you take me to see your invention?"

Tadashi bit his lip.  _Was Hiro well enough to leave the house?_

Tadashi went to Hiro’s side and ruffled his hair affectionately. “Yeah, I’ll take you after main classes; I’ll come back for you during free lab. Sound good?”

"Yeah!" Hiro nodded, seeming to brighten up. 

Tadashi smiled. “Only a few hours,” he promised, standing up and shouldering his bag before leaving.

Later on in the day, Hiro was getting dressed, when he realized how thin he was getting. It had been hard to eat much of anything over the passed few days, but he was determined to change that. He had to keep himself strong. He couldn’t leave Tadashi alone, he refused to hurt his brother.

Hiro was waiting downstairs on the couch for Tadashi, watching some random nature show on tv. He’d taken all of his medicine and had run the oxygen tank for an hour, so he figured he’d be good to leave for a while.

Tadashi was the first one out of his class and hurried out of SFIT to pick up Hiro. He was excited to show him Baymax and put his robot to the real test – yes, the past week he tinkered, tweaked, and tested the bot everyday, but Hiro was the  _real_  test. Tadashi wanted to, both, see his brother’s reaction, and see if he made Baymax advanced enough to cure his brother’s cancer.

“Hey Hiro.” Tadashi greeted as he came inside, putting his helmet and moped keys down he went to Hiro and ruffled his hair lightly. Hiro smiled at him. “Ready to go?”

 “Yep! How was class?”

“Class was boring; the professor was just doing reviews.” Tadashi said with a small sigh, as Hiro grabbed the crutch and used it to help him stand up, leaning against it as he made his way over to his brother. He paused and looked thoughtful, frowning slightly, “Uh…do you think I’m going to have use the wheelchair?”

 “Depends, would you be more comfortable with it? Because I can carry you if you get breathless.”

Hiro shrugged, “I want to to try to walk. I know the doctor said I should use it for longer walks, but I hate being in it. My legs work just fine.”

Tadashi nodded and got Cass’ truck keys before helping Hiro down the steps and into the truck, pretending not to notice the boy's gloomy expression at the unrequested assistance. Once Hiro was settled, Tadashi climbed into the driver's side of the car. The drive was short and quiet, the atmosphere calm.

When they made it to SFIT, Hiro got himself out of the car and to the lab that they had parked close to. Tadashi then helped him up the stairs and to the elevator that lead to his lab, thankful that everyone was too busy with their own experiments to notice them. He knew Hiro was self conscious with his crutch.

He loved to see how the school awed his brother. He’d never seen more than the outside and the showcase building from when they held the annual showcase for the inventors.  
The lab looked amazing, getting to see all those intricate and extraordinary inventions. He knew his brother’s would be better though. He was also glad no one saw them, or paid attention. He always got pitied looks and people would treat him like he was brittle.

He  _wasn’t_.

And he would show that to everyone soon enough.

"This place is awesome!" Hiro yelled as they walked down the hall, a cough wracking his body after the shout. A slight wheeze perpetrating his breaths, and he leaned a little heavier on the crutch, but Tadashi still smiled. He opened the elevator with his ID key and stepping in.

 “I’m glad you like it. Not bad for a nerd school huh?” 

"It’s an awesome nerd school," Hiro nodded, coughing a few times into his hand and having to lean on his knee to catch his breath. Tadashi looked at Hiro with some worry, “Hey, you okay?"

The teen nodded.  
"Just tired...I didn’t think just this little bit of walking would do me in so much…" he tried to smile, as if it were a joke, but Tadashi could tell that he was upset.

He patted his brother on the shoulder. “Don’t push yourself,” he said lightly before the elevator dinged and the doors opened. Tadashi didn't try to assist his brother in walking, as not to make him feel worse, but kept close to him as they made their way to his lab. He swiped his ID again and pushed the door open. 

Hiro looked around, a grin on his face. He sat down heavily in Tadashi's chair, a look of awe on his face. He coughed, rubbing his chest.

"Oww," he muttered.

Tadashi’s eyebrows scrunched together in worry and leaned down to rub Hiro‘s back softly. “Are you-” He stopped as he heard a beeping followed by an inflating sound; he stood up, looking to where Baymax was inflating. Whoops: looks like he forgot to turn Baymax off - oh well. He was excited to see Hiro’s reaction.

Baymax stepped out of his charging station and focused on Hiro before walking to him. “Hello,” he greeted, waving his hand. “I am Baymax, your person healthcare companion.” He lowered his hand. “I heard a sound of distress.” His chest lit up to show ten different faces from happy to agony. “On a scale of one to ten, how would you rate your pain?”

“Hiro,” Tadashi said with a smile, his voice full of pride as he gestured to the robot. “This is Baymax. he’s the project I’ve been working nonstop on.”

Hiro blinked in shock, wheezing softly as his eyes trailed over the robot. He leaned his elbows on his knees, trying to open his airways better.

"He’s awesome!” he exclaimed. "A health care robot, huh? He looks like he has a vinyl covering…what can he do?"

“Baymax.” Tadashi said motioning the robot to continue.  
The screen turned off and the faces disappeared.

“I will scan you now.” Baymax informed and looked Hiro up and down. “Scan complete. You are short-winded; to relieve the pressure in your chest you must rest for at least five minutes and focus on regulating your breathing. You also have a small tumor in your left lung, but luckily with right treatment and a stress free environment it will not spread.”

"Tell me somethin’ I don’t know…" Hiro smirked. 

“Your body produces enough heat in only thirty minutes to boil a half-gallon of water.” Baymax said and Tadashi chuckled.

“He didn’t mean that literally, Baymax,” he informed the robot. Hiro smiled.

He ignored the small aches forming in his back and his left arm and leaned back in the chair as he looked over Baymax with interest. 

"So…you programmed him with the same system they use in the ER,  _and_  he can make quicker diagnostics than going to the hospital. Dude, this is awesome! Do you even realize how great he would be to have in the ER? Heck, on an ambulance? He could tell them what’s wrong in a second and the EMTs would be able to act quicker. You could save a lot of lives with him, especially when he gives back treatments like that." Hiro hummed, standing and circling around Baymax. He pushed his face into the robot's belly. "Titanium skeleton? Nice." 

Tadashi nodded and smiled brightly.  
“Actually he’s an ambulance  _and_  an ER all in one, basically - with the exception of needles of course.” After all it’d be no good if Baymax accident pricked himself and deflated.  
“He has a supply of lollipops and can do anything from minor treatments to defibrillation, and he is also capable of lifting a thousand pounds despite how light and flexible his skeleton is. His only downfall is that he can‘t walk that fast or run," Tadashi continued, before wanting to test the robot further, “Baymax, is there anything Hiro should avoid?”

“Hiro should keep from straining activities, higher altitudes, and anything with peanuts due to his slight peanut allergy though it wouldn’t be dire.” Baymax said.

Hiro listened intently, watching Baymax’s movements with a calculating gaze and grinning. Gleeful eyes turned to Tadashi, “I knew you would create something amazing. He’s like a giant marshmallow. I wish there was one of these guys every time I went to the hospital, maybe then it wouldn’t be so freaky.” he chuckled.

The boy examined Baymax a little more, poking him in places to test the vinyl. It was amazing how nearly flawless he was. No wonder it took Tadashi so long to work on him. Unable to reach his crutch, Hiro sat back down.

"We might need to go home soon," Hiro admitted, "I’m getting pretty tired. But I think Baymax is amazing. You did a great job with him, Tadashi. The San Fransokyo Children’s Hospital is having their annual convention. You should totally enter into their robotics contest and see if they’ll put him into the staff! It’d make a lot of kids feel more at ease, especially in the cancer wing."

“Well, I’m glad you like him…because he was built for you.” Tadashi smiled happily. “Maybe he would be helpful for others and I’m glad about that, but this Baymax is one of a kind and I built him with you in mind. Who knows, if you really like him then I might make some similar.” He informed, smiling as he noticed Baymax was poking his stomach in a way similar to how Hiro did.

 “No more cold hospitals and unknown doctors.” Tadashi continued before hearing the door open a split second before he was pulled into a tight hug.

"We’ve missed you!" Honey Lemon said happily. "You haven’t been coming to open lab, so when Gogo said she saw you, we had to come by!"

“Yeah, I’ve been working on some things outside of the lab.”

"I see your marshmallow man is working," GoGo popped her gum, "Nice."

"And who’s this little guy? A friend of yours?" Wasabi asked, smiling at Hiro.

"Uh…I’m his little brother, Hiro…" he said shyly. Honey gasped and rushed to the younger Hamada, hugging him as well.

“So you’re Hiro? -We’ve heard so much about you!” she exclaimed gleefully, letting him go and pushing her glasses back up.

“Come on Honey, don’t scare him away now.” Gogo said though her voice kept neutral.

“What’s up little dude?” Fred greeted before looking to Baymax in wonder. “Dude, this robot is so soft!” he exclaimed to Tadashi, hugging Baymax and leaning against him.

Hiro blinked at all of the people, looking between them and his brother. He hasn’t even known Tadashi had friends. Well, he was sure he had to have _some_. Tadashi was a very likable guy, but he’d never heard anything. It made him smile slightly, glad his brother had people who would be there for him.

"All good things, I hope," he told Honey once there was a brief-second interval for him to speak. He kept his voice low so it wouldn’t croak, sneakily kicking his crutch under Tadashi’s desk so it couldn’t be seen. Hiro didn’t want Tadashi’s friends to know.

"Just that you’re a freaking genius!" Fred exclaimed with glee, letting go of Baymax. "Man, graduating high school at 13? That’s amazing!"

"It’s impressive," Gogo nodded, "Heard you’re pretty good with robotics too."

Hiro leaned back and blew on his nails, polishing them against his chest, “Well, ya know, I don’t like to brag, but yeah. I am pretty good.”

"You’ll have to show us some time," Wasabi chuckled, patting the boy gently on the back. The vibration it caused through his chest made sudden pain shoot through his lungs and made them tighten. Hiro winced slightly, coughing into his hand.

“Are you okay?” Wasabi asked before looking to Tadashi. “Is he alright?”

“Yeah,” Tadashi said, looking to his brother worriedly, noticing the hidden cane and understanding he didn’t want them to know.  
“He’s just a little sick.” Tadashi covered.

“What?!” Wasabi exclaimed, jumping away from Hiro. “Why didn’t you say that in the first place?”

Tadashi chuckled lightly and went to stand next to Hiro before going on to introductions. “Okay, so Hiro, these are a few of my closet friends. That’s Honey Lemon; she’s the best chemist I know.”

Honey blushed lightly. “Well I wouldn’t say best - but I am good at what I do.”

“This,” he motioned to the dark-haired girl, “Is Gogo. She’s into mechanical engineering and is currently trying to make the fastest bike with no resistance.”

“Sup,” Gogo said, popping her gum.

“This is Fred, he gave everyone their nicknames, and is SFIT’s mascot along with comic and science enthusiast - I’ve known him since high school.” Fred just held his hand out for a high-five. “And the person slowly backing away is Wasabi. He’s planning to major in applied physics.” Tadashi leaned towards Hiro to whisper the rest. “Major OCD and germ-freak.”

Hiro waved at each person as they were introduced, chuckling at Fred and giving him a high-five back.

"It’s nice to meet you all," Hiro smiled softly. "It’s also nice to know that Tadashi actually has friends. Here I was thinking my brother was a nerdy hermit.."

The group laughed lightly. “He is sometimes; we thought he was doing it again when I saw him sneak in,” Gogo offered with a small smirk.

“Oh ha-ha.” Tadashi said rolling his eyes before sighing. “We were about to go anyways before Hiro gets any sicker.”

"Aww, well, we’ll let you guys go." Honey said politely, "Sorry for just barging in like that."

"You gotta keep in contact more, man," Fred said, "We’re your amigos! Can’t leave us hangin!"

Hiro smiled gently, “I’ll make sure he doesn’t lock himself away so much, okay?”

"Thanks, little man," Fred grinned, "Hope ya feel better."

"Thanks." Hiro smiled.

The group said their goodbyes before heading out of the room. He was so glad when they were gone, because he leaned over against Tadashi and groaned softly. “Can we go home now…?”

Tadashi smiled at Hiro as he leaned against him and ran his fingers through Hiro’s hair soothingly. “Of course… Baymax, can you please carry your charging chamber with us?” He requested.

Baymax nodded and went to the red box, closing it and shutting it down before picking it up with minor difficulty due to how inflated he was and how short his legs were.

Tadashi smiled before getting Hiro’s crutch and turned to pick him up. “We’ll go out the back so your new friends won’t see,” he said playfully as they walked out, going a different way that no one used. Soon they were at the truck and Tadashi helped Hiro in before taking the charging station from Baymax and setting it down. “Since you activated him, I need you to say ‘I am satisfied with my care’ so he can deactivate for now.”

"I am satisfied with my care," Hiro repeated and watched as Batnax deflated into his charging holder. He snorted softly. "He is so cool."

Tadashi smiled and picked up the charging station once Baymax was put away. “I’m glad you think so.” He admitted his relief, putting the box in the middle seat before going to the driver’s side, getting in and driving them home.

When they got home, Hiro helped Tadashi get Baymax’s charger upstairs into their room. He was a little winded by the time they got there, but nothing he couldn’t deal with. He hugged his brother as soon as the luggage was set down, smiling happily. 

"Thank you so much," he murmured, "For working so hard and spending so much time on something like this for me. You are seriously the most brilliant inventor there is."

Tadashi smiled and hugged Hiro close. “Thanks Hiro… And it was no problem at all.” He said, pulling back and smiling even brighter. “I know you get lonely, and he doesn’t seem like he’d be that fun, but he’s adaptable, he can learn so you won’t be lonely.” He didn’t want to mention his hope for Baymax to find a cure for Hiro because he didn’t want to get his hopes up when he wasn’t even sure if Baymax could at all.

Hiro smiled softly, “Good, so that means you can go and hangout with your friends more.”

When Tadashi frowned, Hiro faltered.

 “I know you worry so much about me, but I’ll be fine. Once the tumor gets a little smaller, they should be able to do surgery to remove the part of the bronchial tube where it’s at and then it’ll all be better. In the mean time, you can’t be pushing your friends away and avoiding living your own life. Even…even if by the off chance I don’t get better, you need to have people you can rely on if that happens. These guys seem like pretty good people and they seem to really care about you. Don’t lose that…please. You need people to be there for you to. You can’t just bare all this weight yourself. You and Aunt Cass can’t do this to yourselves.”

Tadashi blinked and was at a loss of words at what Hiro said. That wasn’t right. Tadashi didn’t want Hiro to think that. He liked his friends, but he loved spending time with Hiro, Baymax was so Hiro could have some independence since Cass and himself won’t constantly be worrying because they’d know Baymax would take care of it.

“Hiro…” He started, thinking of the words carefully before talking. “I love spending time with you and that’s not going to change because of Baymax. I’ll spend more time with them if you’d like, but I want to spend a lot of my time with you - I know I’d regret it if anything were to happen…”

Hiro sighed softly, “I know…I just…I don’t want to hurt you worse if things don’t go the way we hope…  
"Cass got a call from my doctor earlier and he wants me to stop taking the medication I’ve been on. Since it’s experimental, they don’t know what its long-term effects are. They’re afraid it’s making the anemia worse and until they can do more studies, he doesn’t want me on it anymore." He had wanted to wait until after everything to finally tell him, so that his brother wouldn’t worry worse. The medication had been what had helped keep the tumor small.

Tadashi pressed his lips together at the information and tried to remain neutral through all of this new information, he knew Hiro didn’t want him to worry or freak out…

He sighed and put on a small smile before hugging Hiro close. “It’ll be alright, I just know it Hiro. You’re too strong to let this knock you down… Are they going to give you a substitution or are you clear off of meds?” He asked curiously.

"He’s going to come by tomorrow and give me a check-up before seeing what can be used as a substitute." Hiro told him and made a face. "I’ll take anything he wants so long as they don’t make me do chemo anymore. I hate how tired it makes me feel."

Tadashi smiled lightly. “I know you don’t like drowsiness.” He said ruffling Hiro’s hair some. “When did you find this out?” He asked, genuinely curiously. If it was today…that’d explain the mood Hiro had been in.

He shrugged, “This morning while you were in classes. Aunt Cass got the call before she came to wake me up. I wanted to wait till we got home to tell you, because I didn’t know if you’d still let me see Baymax or not.”

Tadashi sighed lightly. “I wouldn’t have,” he admitted before continuing. “I would have brought him to you instead. I finished Baymax that night you were sent to the hospital, but…I wanted to give you some incentive.”

Hiro gave a small chuckle, “You don’t have to worry about giving me incentive. I fight because I want to. I don’t want to leave you guys and there’s a lot of things I still want to do.”

"For instance…" he took a small calming breath, "I want to get into SFIT."

Tadashi smiled brightly. “Really?” He questioned before hugging Hiro. “I’m glad…” Tadashi admitted, thinking of the good things that could come from Hiro having a new goal.

Hiro nodded and hugged him back, “I want to be able to build things to help people…like you’ve done with Baymax. I had an idea…of building a robotic guide dog that would be able to help people with disabilities. It’d be able to lick someone’s hand and tell them their blood sugar and pressure levels. It could talk to people who are blind. It’d be able to communicate with people who are deaf to translate for them, even be able to alert the police or a medic if the person was in danger, even before the person knows it. It’d be able to help people live independently so they wouldn’t have to constantly be worried about the world around them. And that’s only one of my ideas, I have a lot more too.”

He pulled away to cough a few times into his hand, all the fast-talking hurting his chest with the quick breaths, but he was so excited to tell Tadashi. And it was the first time in a long time he’d seen his brother’s eyes so full of life. He wanted to keep it that way for as long as he could. 

“Oh, Hiro, that sounds great!” Tadashi said enthusiastically, this was amazing to him - Hiro was so hesitant to go outside, let alone go to school.  
“I’d love to hear more, if you ever want to tell me- ah! I’ll ask about enrollment on Monday.” There was always the fair, but Tadashi wanted to check other options as well.

"Okay," Hiro grinned excitedly, he couldn’t wait. Then he’d finally be able to work with his brother.

 


	5. Meet The Dynomutt

**Summary for the Chapter:**

> Hiro gets started on his project for the SFIT showcase.

**Notes for the Chapter:**

> Hey guys! Thanks so much for the positive feedback! I'm so glad you're liking it. Keep giving me your thoughts, it's always helpful! Enjoy :)

The next day, the doctor came by and checked out Hiro, finding another medication to give him to help with the coughing and the tightness in his chest. After the appointment, he helped Cass in the cafe for a little bit, before going up and starting to work on his blueprints for the projects.

Tadashi waited until Hiro’s appointment was over to head to SFIT. He didn’t have classes today and thought about taking Hiro, but quickly busied himself.

He returned about two hours later and went upstairs, two steps at a time.  
“Hiro!” Tadashi exclaimed happily, going to his brother. “Okay, so I found two ways. One involves making an invention and showing it off in a showcase, and the other is through a meeting with five different professors to talk about yourself and what you want to do. Both are open to you.”

Hiro looked up and blinked in surprise, “Really?” Both of those options required talking, something he didn’t like doing too much of on certain days. If his appointment for one of them fell on a bad day, he didn’t know how long he’d be able to make his case. He was slightly worried about that, but he could figure a way around it, somehow. 

"Would you help me?" he asked his brother, knowing there was no way he was going to be able to build thing on his own. Hiro was amazing with coding and blueprints and putting big pieces together, but his anemia, which was a side effect of the cancer, made it difficult to focus on small things like wiring or small parts. He knew he was going to need help. 

“Of course I’ll help you-when you need me that is.” Tadashi agreed with a bright smile before rolling his eyes some.

"Oh," Hiro suddenly remembered, frowning at his brother, "You didn’t tell them anything about my situation, did you? I don’t want to be a pity case."

 “I didn’t. I know you don’t want to be judged differently or given an advantage. All they know as of right now is that I have a brother interested in attending SFIT. Whatever else you want them to know is going to be up to you. They won’t pry for information like the grade-level schools.” He assured. Hiro sighed softly, “Good.”

"Hey," Hiro poked him in the stomach and turned back to his desk, motioning Tadashi closer, "I started on my blue print for the robotic guide dog. I can’t come up with a name for him though."

Tadashi took the hint and looked over Hiro to the blueprints and smiled. “If you want Fred to freak out you can call it Dynomutt but it wouldn’t be good to anyone else who got the reference.” He said before humming as he thought about a name. “I don’t know… I’m not very good at naming.”

"I don’t know," he sighed softly, but smiled, "I’ll think of something."

Hiro worked on the project for months. It was a slow process, but it was gradually coming together. He spent most of that time with Tadashi, getting his brother’s help things he knew he couldn’t do. The best part for Tadashi was seeing Hiro smile so much. He’d never seen his brother happier, and he knew he would be beaming when his little bro got into college.

There were still good and bad days in between, though. Somedays Hiro wouldn’t want to get out of bed because of how tired he was or he’d have small spells of his chest tightening and having to breath through the tank. It didn’t stop him from pushing himself and doing small bits of work when he could on those days. Sometimes, when it was a really good day and Tadashi was at school, he’d help out in the cafe and Hiro hadn’t seen Cass smile like that in a while. He was ecstatic, as was Tadashi. He and Hiro were spending time together and working on his project. 

In fact their whole home seemed in a better mood. Everyone was happy and worries were few.

“Okay…” Tadashi hummed as he finished the wiring. Once he finished he closed the hatch and smiled at Hiro. “Wiring is done. Ready to test it?” He questioned Hiro lightly as he stepped away and went to stand next to his brother, leaning down to activate the dog and little lights lit up in its eyes.

Tadashi noticed how Hiro held no hesitation and remembered his own first test. Oh, how he hoped that the dogbot worked, he didn’t want Hiro to feel defeated after all the work they did. It _should_ work - Tadashi learned his mistakes with Baymax.

"Hello," it said in a kind robotic voice, "I am your personal care assistant."

"He works!" the teen grinned, "Once I come up with a name we can program it into him, but he works!"

Tadashi watched and cheered with his brother before hugging him. “Good job, little bro!”

"Hey, it wouldn’t have happened without you," Hiro hugged him back and then turned off the bot, smiling tiredly at his brother. "Only a little over a week left until the showcase. I can’t wait to blow them all away with this. And then I’ll be able to work with you in your lab!"

"Speaking of which," Hiro checked the time and it was only a little after three, "Wanna see if the gang wants to hang out?"

Over the passed few months Hiro has been spending more and more times with Tadashi’s friends, who had been slowly becoming his friends too. Hiro hadn’t really had anyone other then Tadashi and Aunt Cass in his life, so it was nice to have friends. It was surprising how much good all the work was doing him, too; Hiro’s doctor had said he was in more stable health with the goals and positivity all of this had brought.

 “Yeah, sure. It’s a Saturday so they shouldn’t be doing much.” Tadashi agreed and grabbed his phone to make a group text and texted the others if they wanted to meet up somewhere.

“We should go get Baymax and rescue him from Mochi.” Tadashi half joked. The healthcare robot activated one day because of Cass and neither of the boys had it in them to deactivate him. Since then Mochi took a liking to him and claimed the giant marshmallow as her bed - luckily she knew better then to use her claws on him.

Hiro laughed, “Yeah, but I think he likes her a lot too. He always calls her ‘hairy baby’.”

“That’s because she’s a dependent cat and Baymax’s job is to help so he finds it important to keep her happy and warm.” Tadashi countered with a laugh. He never made a clear line between people and pets so Baymax would help anyone.

Hiro followed his brother upstairs to the house, hunching over once they got up the stairs and putting his hand son his knees as he tried to catch his breath. “H-hold…on….” he panted.

Tadashi stopped halfway up the stairs and went to Hiro in worry. “You okay?”

"Y-yeah…" he panted "The first flight just winded me…"

He leaned on Tadashi and put a hand on the wall. They just had the stairs of their room to get up, but his lungs were not happy with the thought. He panted heavily, taking deeper breathes to try and relieve some of the pressure. It didn’t help much, though, and then sharp pain stabbed through his lungs.

He doubled over coughing, hard and breathless, wheezing between each as he fell into Tadashi and tears welled up in his eyes as he coughed.

Tadashi caught Hiro and patted his back. “I think it took more out of you then you think…” He said softly before picking Hiro up and carrying him the rest of the way up. “Baymax, I need you to scan Hiro.”

Baymax looked up as Tadashi laid Hiro down and had Mochi get off of him before going to the younger and scanning him. “Hiro has become short winded from too much excitement and exercise. He should be fine in a few minutes if he breathes correctly. Shall I get his tank?”

Hiro nodded, rolling onto his side on his bed as he coughed and gasped. When Baymax got the tank and the mask was put over his mouth. He breathed in the oxygen, coughing still, but it slowly started to calm down. It took a good fifteen minutes before his breathing started to ease.

"Whoa…have not had one of those in a while…" Hiro breathed, still taking in air from the tank as he rubbed the tears and sweat from his face.

"I recommend bedrest for the duration of the day, so as not to further irritate your lungs," Baymax said.

Hiro shook his head, shakily pushing himself up, “No…I’ll be okay…I’ll be okay…”

“No.” Tadashi said, gently pushing Hiro back down. “Hiro, relax. It’s only a day - it’ll be fine. We haven’t told the others yet. What if you have another attack while we’re out? You’ve had an amazing streak this time and I’m proud, but you need to be in top form to show off your invention. We can reschedule with the others.” He reasoned in a soothing voice.

Hiro frowned, but relented and nodded, “Alright…”

He wanted to argue, but he knew Tadashi was right and he didn’t want to screw up things now. It was only a little over a week before the show, and he was doing so well. So, if he just needed a day, he’d deal.


	6. Race Against Time

**Summary for the Chapter:**

> Timing is an ass.

But it sadly wasn’t just a day.

The next day he was too weak to get out of bed, too tired to do anything. He was coughing more and more recently. It was three days before the show when Hiro collapsed with a fever and shallow breathing.

According to Baymax’s scan, the tumor had grown.

Tadashi remained calm around Hiro as Baymax made the report and calmed his brother down. However, once the younger Hamada had fallen asleep again, Tadashi stormed into the garage, pulling Baymax behind him. He cursed in ways he normally wouldn’t as he worked on the robot, trying to push his technology to its limits, until he collapsed in tears.

_Why was this happening?_

Why now, when Hiro finally had a reason to fight the cancer? Why did he lose his parents and now was losing his little brother? It wasn’t fair!  
He was nice - some even called him a saint - so why was _his_ world the one crumbling down into tiny little pieces he had no hope to put back together.

Why was nothing he did _ever_ enough?

Tadashi shook and withered as he curled into himself, feeling nothing but despair and coldness, even as Baymax hugged him close and produced heat.

Cass called the doctor the next day and after confirming the diagnosis, he scheduled immediately for the boy to be taken to the hospital for treatments.

"I can’t go…" Hiro murmured at the doctor.

"You don’t have a choice, son. We need to begin treatments if the tumor is going to grow like this." The doctor frowned.

He shook his head, “It’s two days before the big SFIT showcase. I-I’m going to get in and I’m going to go to school with my brother and work with him. I don’t have time to go to hospital.”

"But Hiro, you have to," Cass frowned.

Hiro shook his head stubbornly, “No. I’m not going. I’m going to stay here and work on my project and I'm going to be there.”

"Hiro, you’re being unreasonable. You can’t go to that showcase. What if you don’t get in? What if you go into a coughing fit on stage? You could hurt yourself: you _can’t_ participate," the doctor said firmly.

"No!" the boy hissed.

"Hiro!" Cass frowned gently. Oh, where was Tadashi? He was so good at handling his brother.

Just then Tadashi was coming in from the garage, walking up the stairs lazily when he heard the arguing and stopped where he was, hand on the wall. His grip tightened on the railing at the doctor’s words. That’s what he hated about doctors; they were too rough when their patients didn’t need that!

Hiro just needed time!

Tadashi walked the rest of the way up. “Doctor, forgive me because I’m no professional, but are your words supposed to help my brother - when not even a week ago you said that the goal was helping him?” Tadashi questioned, his voice slightly raspy from crying his heart out last night, but luckily his appearance seemed normal. If he could just keep it out of his voice then he’d be fine; after all, he was good at masking his problems.

“You can’t _legally_ force Hiro to go anywhere he doesn’t want to, and from personal experience, I can guarantee you he’ll find a way to be at the showcase anyways. Besides, mental health is just as important as physical. I believe my brother won’t fail/ I think he’ll do amazing. And if you want to talk any further then I want a consular with you,” Tadashi said before turning to Baymax, who came up with him. “Baymax, take Hiro to the garage.”

“But Tadashi, you bl-”

“Baymax… Please.” Tadashi said desperately and the robot complied, carefully picking up Hiro and carrying him downstairs with Tadashi not far behind them.

"Tadashi, please," Cass grabbed his arm to stop him, "I know just as well as you do that Hiro is going to do whatever he possibly can to go and participate in the showcase, but he _can’t_. I know that he can do this and I know that he’ll get in with no problem. But this medication isn’t working, and he’s been miserable the past few days. You saw how hard it was for him to even sit up for the examination today! What will hurt him more than not going, will be going up there and having a problem and then _not getting in_. If he passes out or has a fit, they won’t judge his invention and he won’t get in, and that will devastate him." She explained quietly and sternly.

"I agree, the doctor shouldn’t have acted or said what he did," Cass glared at the man before looking back at Tadashi, "And this goal has been the best thing to happen to Hiro. But, it would be better to have him strive for the next showcase and even improve his invention in that time, than have them disqualify him and break his heart. I’m terrified that if something happens and he doesn’t get in, that he won’t have the will want to fight anymore." Cass told him, tears in her eyes.

She was at her wits end too. She was terrified of losing her youngest nephew and it was killing her to see him suffer. She just wanted to do whatever was the right thing to make him better and keep him happy.

"He’s already upset enough about the growth," she sniffled, "I don’t know what is the right or the wrong thing to do, Tadashi. I just want him to be okay."

Tadashi dropped his act to hug her close. Hiro and Baymax were out of the house already anyways. “I know… I’m scared too and I want him better…but if…if he is going to be forced to leave us then I want it to be on his terms. Not depressed and in a place he hates. Please Cass… We both know that if he does fail then he’ll try again, but if we don’t allow him to go, he’s going to be angry and upset at us.

“Putting him in the hospital will do nothing - yes they have medicine, but that’s only for the physical problems. You know as well as I do, the most Hiro will stay in a hospital is a day before he’s driven into deep depression,” Tadashi pointed out sadly. “You know I wouldn’t do this for no reason.”

"I know, I know sweetheart," Cass breathed, sighing softly as she wiped at her eyes and hugged him tightly. "I’m just…I know. I want him to go through with this. You two have worked so hard and I’m so happy for him to have something he’s aiming towards."

“But it’s too much of a risk. He could over-exert himself and cause further problems. As it is, his fever is too bad to be doing something like that. I know he doesn’t like being in the hospital, but he has to of he wants any chance of surviving," The doctor argued.

"Okay, okay this is what we’ll do," she decided, turning to the doctor, "The day after the show case, he’ll come by the hospital for tests and a treatment, but he is going home after. Yes, he is going to that show and he is going to blow away those judges and dammit, my nephew is getting into that school, got it?" Cass huffed.

"Fine," the doctor frowned and packed up his stuff, storming out after.

She sighed heavily and covered her face. This couldn’t get any worse. Tadashi hugged her again.

 “Thank you Aunt Cass, and I know Hiro and I don’t say it enough but, I love you.” He said, kissing her cheek before pulling away with a small sigh. “Don’t worry. Hiro will make it through this - I know he will,” Tadashi said confidently and kissed her cheek again.   
Cass kissed him in return, “I love you boys with all my heart, you're both my entire life. I know he’ll make it, as well: you boys have your father’s spirit. My brother never gave up on anything and I know neither will you two.” Tadashi smiled and nodded before going downstairs to the garage.

Baymax had laid Hiro down on the couch and seemed to be guarding over him when Tadashi entered.

"Hello, Tadashi," Baynax greeted. Hiro was lying sleepily behind him, his oxygen tank running and he frowned at Tadashi.

"T-they’re going to make me drop the showcase, aren’t they? I don’t want to go back to the hospital! Please don’t make me," He begged weakly.

Tadashi sat on the floor next to the couch before reaching up to comb his fingers through Hiro’s hair and smiling.

“Don’t worry, otouto. Cass and I talked and we sent the doctor away. We’re not making you give up the showcase - not when we both know you worked so hard. Besides, we both want to see you go up there and blow everyone away.”

Hiro leaned into the combing fingers and gave a few weak coughs. “Good. I’m glad…I wanna make you proud. But, do you think there is anyway they’d let me sit in a chair and explain my invention? The showcase is tomorrow night and I don’t think I’m going to have enough strength by then to stay standing that long.” While Hiro hated admitting weakness, he knew that especially because of the fight he'd put up with the doctor, he needed to be realistic as to what he was capable of.

Tadashi smiled. “Yes, they let you set the area as you like and if you do it right you can use that to your advantage.”

Hiro smiled, “Good. Tomorrow will be awesome!” Tadashi let out a small laugh.

“Yeah, it will be.” He agreed, kissing Hiro’s forehead, being mindful of the oxygen mask. Hiro closed his eyes, snuggling into the couch. “I love you, Nii-chan….”

Tadashi smiled and pulled back to run his fingers through Hiro’s hair again. “I love you too, otouto. Soshite, nani mo sore o henko shimasen.”  _(And nothing will change that.)_ He said affectionately.

Hiro smiled slightly and closed his eyes to sleep.

**Notes for the Chapter:**

> Up next: the showcase! Get excited!


	7. Teenage Mutant Scientists

**Summary for the Chapter:**

> The showcase!

Today was the day of the showcase, and Hiro was excited. He settled on naming his dog-bot Rex, and he and Tadashi had fixed up his voice to be softer and informative, but friendly. They just needed to figure out how they would set up the stage.

Tadashi had hardly gotten any sleep, having stayed up working on Baymax, but luckily for him he was used to it. He focused his attention on his brother.

“If you set up the seat in one of the corners, you can demonstrate Rex’s ability to lead and play it into your presentation if you need to.

"I like it," he nodded, "and there’s a shadow near the stairs to the stage, right? We can hide Baymax there with my tank, can’t we? I’ve figured out that I can talk for ten minutes before my chest starts to hurt. To avoid coughing, I’ll have to use the programming to get Rex to explain the rest of the presentation."

“And if it becomes too much you could always use the tank as a ‘display’, to show that words aren’t needed for Rex to communicate.” Tadashi added with a smile. “I think you got this, Hiro,” he said happily, ruffling Hiro’s hair lightly.

Hiro smiled happily, “This is going to be awesome, Tadashi. I can’t wait. You’re going to show off Baymax, aren’t you?" He asked.

Tadashi shook his head. “No, Baymax is still a work in progress. I only wanted you to see him, but I guess it was inevitable for our friends to see him as well.”

"Well, he’s going to be even more cooler when he’s all done," Hiro grinned.

The day went by in a blur, yet agonizingly slowly at the same time. Tadashi helped Hiro get everything set up on the stage and were waiting for the teen’s turn to come up.

Hiro was anxious and his worrying wasn’t doing much to help his already-aching lungs. He sat on the floor in the shadow near the stage with Baymax, Rex, Cass, and Tadashi, breathing through the mask of his tank. He leaned forward with his arms stretched out, trying to open his lungs enough to get through the presentation.

Tadashi was sitting next to Hiro, rubbing his back soothingly. “Don’t worry. I’m going to stay right here with Baymax.”

Hiro nodded, taking deep breathes and letting them out slowly, counting as he did so. “I just don’t…don’t want to mess up. I don’t want to let you down. I know you put a good word in for me, and I don’t want to mess things up for you.”

“Psyching yourself out won’t help,” Tadashi pointed out before smiling. “You won’t let me down, Hiro. I know you’ll be amazing. You’ve just got to have some faith in yourself.”

Hiro nodded, breathing in and out. It took a few more moments until his chest loosened enough for him to breath clearer. “Okay…okay, I can do this.” He nodded confidently to himself.

“You can do this,” Tadashi agreed with a nod and a smile before Hiro’s name was called.

Hiro took a few last deep breathes before pulling away the tank and slowly standing up, smiling at Tadashi as he lead Rex up to the stage and they began the presentation.

It went off without a hitch, the judges loving the dog and the crowd looking amazed. Hiro and Rex left the stage and the boy set a hand on the wall for balance. The dog licked his hand and barked softly.

"Your blood oxygen levels are severally lowered," he warned.

"I know, I know," he panted and then looked up and smiled tiredly at Tadashi. "We did it! I think we did it!"

Tadashi stayed with Baymax behind stage while Cass went to join the crowd. He watched from their, smiling as his brother and Rex easily got everyone’s attention.

Tadashi waited until Hiro was off stage to hug his little brother close. “I told you you’d do awesome!” He exclaimed before letting go as Baymax came over and helped Hiro get the mask on before turning it on.

“Hiro did well. Though your oxygen levels are low and your heartbeat is irregular, your lungs seem fine and normal with no growth in the tumor.”

Hiro smiled tiredly, leaning into his brother’s chest as he breathed deeply through the mask, closing his eyes.

"You were right," he panted out, really glad to hear the scan from Baymax. No growth meant no hospital and no fluid. "Phew. ’m exhausted now."

Tadashi supported Hiro gently and ran his fingers through his hair soothingly to get him to breath calmer.  
“Well, once your oxygen levels are back up we can go looking for Cass and she can drive us home and you can sleep.”

"I like that idea," Hiro chuckled breathlessly, leaning into his brother’s chest as he closed his eyes. It took a few minutes before his breathing was under control, but he finally did and thankfully by then Cass had found them.

"You did great, baby," she told Hiro, kissing his head. "And you look like you need a good rest."

He nodded, smiling weakly, “Yeah, but this was worth it.”

"Yes it was sweetie, and I couldn’t be prouder," she smiled at him, motioning for the boys to follow her to the truck.

 “The judges will make their decision tomorrow.” He said patting Hiro‘s back as they walked out.

The small family headed towards the truck, but were stopped by the sound of their names being called. 

"Hiro! Tadashi!" Tadashi’s friends rushed over, grinning. 

"Hey! We were trying to find you after the presentation - that was amazing!" Fred said happily, "Rex is epic!!"

"Yeah, you did a really great job on him, Hiro," Wasabi smiled, "We wanted to congratulate you for doing so well."

"I didn’t know you were going to try to go to school here! This is exciting!" Honey grinned. 

"Nice idea, squirt," GoGo popped her gum, "At least its not a giant marshmallow," she teased, winking at Tadashi, who pouted playfully.

“What? You don’t like the huggable design and the fact he can pick all of us up no problem? Or maybe it’s the portable heater part?” He questioned before chuckling and smiling.

"Nah, the dog’s cooler," she replied

Hiro grinned at them, “Thanks guys, I really appreciate hearing that from all of you. I’m glad you like him so much.”

"He’s adorable," Honey giggled, petting Rex and smiling as his metal tail wagged happily. "He’s going to be very helpful to a lot of people."

Hiro nodded in agreement. 

"I’m so glad you guys got to see his presentation," Cass said happily, "And thank you for coming to congratulate him. That was so sweet of you all."

"Well, he’s our friend, we can’t just _not_ be there to support him," Wasabi chuckled.

The teen’s eyes glittered with happiness at the idea of having friends. So they really had accepted him into their group. Hiro finally felt some semblance of normalcy in his life and he couldn’t be happier. He startled a little put of his thoughts as Cass patted his shoulder and then motioned for him to get into the truck. 

"Well, it’s been a long day and we need to be heading home," Cass told the older teenagers. "It was so nice seeing you all."

"Nice seeing you to," Honey smiled and gave the Hamada’s all hugs. "Congratulations again, Hiro. I know you’re going to get in."

The others gave their congratulations and goodbyes before walking off so then the family could get their robots in the back of the truck and then they could climb in to. As they pulled out of the parking lot and started towards home, Hiro snuggled into Tadashi’s side and sighed softly, happy and content. 

Today was a really good day…he hoped tomorrow was the same.

**Notes for the Chapter:**

> I decided not to have the fire, although I might makes some sort of parallel later on. I also skipped over the details of Hiro's presentation just because I wanted to keep the story moving. Thanks so much for all the nice comments and support! Hope you guys are enjoying this :)


	8. No Good Deed Goes Unpunished

**Summary for the Chapter:**

> The day had gone by in a blur. Tadashi remembered grabbing Hiro by the shoulders and screaming his name, and then Cass was there, pulling him away from the bed and frantically calling emergency services. Baymax helped as much as he could and was able to keep Hiro stable until the ambulance arrived.
> 
> His ears were ringing and he was in shock for one of the longest car rides of his life as Cass drove to the hospital. When they arrived, Hiro was rushed into the emergency room and Cass and Tadashi were left in the waiting room at the mercy of his terrified thoughts. 
> 
> This couldn't be happening, Tadashi thought to himself frantically. He couldn't lose Hiro, not now, not after how much work they had put into Rex and had made it through the showcase. He couldn't give up now!

The next morning, Cass went to wake the boys up. She came over to Tadashi’s side, sitting on the boy’s bed and combing her hand through his hair lovingly. “Time to wake up, sweetie,” she said softly, leaning over to kiss his cheek and shake his shoulder gently. Tadashi’s eyes slowly opened and he couldn’t help but smile. It had been a while since Cass did this, and it was very much welcomed.

“Good morning Cass.” He greeted before she moved to wake Hiro and he sat up.

"Time to wake, sweetie," she repeated softly to her youngest nephew, combing her hand through his hair and pausing, furrowing her brows at how damp it was. She felt his forehead and came away with a fever, then she noticed the clear tube running over the side of the bed. Cass moved the blankets slightly, earning a groan from the boy, and saw that he was sleeping with his oxygen mask.

"Babydoll," she brushed his bangs from his face, "Are you not feeling well today?"

Hiro gave a weak shake of his head, cracking tired dark eyes open to look up at her.

“Not really,” He croaked. “I don’ wanna get out of bed today…please?”

"That’s okay," she consoled with a small, worried sigh, "You can stay in bed today. I’m going to get you some water and Tylenol, okay?"

"'Kay," he breathed as she stood up. Once Cass was gone Tadashi sat on the edge of Hiro’s bed, “You okay?”

"Not really," Hiro repeated, looking at Tadashi blearily and coughing a few times, "I just feel really tired and sore….I think I might’ve caught a cold or something last night.”

Tadashi ran his fingers through Hiro’s sweat-dampened hair. “Do you want me to get Baymax or Rex to keep you company?”

"Can’t you stay?" he croaked, coughing again softly and making a small noise of pain. "Ugh. This sucks."

Tadashi smiled lightly. “Okay, otouto. Of course I can stay.” He promised. If Hiro wanted him to stay, he’d stay. Hiro hummed gratefully.

Cass brought him his medications and a glass of water, helping him swallow the pills and foul-tasting liquid and then convincing him to rest some. Tadashi stayed by Hiro’s side all day, and he was glad he did. Hiro twisted fitfully in his bed, his face pale and clammy. Tadashi had pulled a chair by the bed and was doing homework, when he heard Hiro groan. He barely had time to jump out of his chair before Hiro rolled over and threw up all over the floor.

“Hiro?” Tadashi called his brother’s name worriedly, carefully avoiding the vomit as he rubbed the boy’s back soothingly. Hiro collapsed back on the pillows, groaning. Tadashi repeated his name a few more times, but the boy didn't seem to hear him, his eyes soon slipping shut as he fell into another fitful nap.

Tadashi cleaned up the vomit and gently wiped Hiro’s face with a washcloth, replacing his now-spoiled shirt with a fresh one. He noticed how thin the teen had gotten, but tried not to dwell on it too much as he made sure Hiro was comfortable.

Hiro vomited several times throughout the day, and after the second time Tadashi kept the trashcan by the side of the bed, remaining close by to ensure that Hiro didn’t choke on his own vomit. At one point he had to hold Hiro up so that he could retch into the trashcan, the boy’s frail body shaking in his arms as he coughed and spluttered as Tadashi fretfully smoothed Hiro's damp hair back from his forehead.

Tadashi held Hiro’s hand as the boy slept; his thick, irregular breaths audible, his scrawny chest heaving and trembling. Tadashi watched him worriedly.

Around noon, Tadashi was starting to nod off. But then his subconscious noticed that something felt off, and he blinked and glanced around, trying to see what was wrong.

Then he realized what it was, and his heart exploded in his chest: he could no longer hear Hiro’s raspy breathing. He jumped out of his chair, his ears ringing. 

Hiro wasn't breathing.

The next few hours were a blur.

He remembered grabbing Hiro by the shoulders and screaming his name, and then Cass was there, pulling him away from the bed and frantically calling emergency services. Baymax helped as much as he could and was able to keep Hiro stable until the ambulance arrived.

Tadashi's ears were ringing and he was in shock during one of the many longest car rides of his life as Cass drove to the hospital. When they arrived, Hiro was rushed into the emergency room and Cass and Tadashi were left in the waiting room at the mercy of their own thoughts and fears.

Tadashi sat hunched over in his chair, rocking back and forth to calm himself.   
It didn’t help.

 _This can't be happening,_ he thought to himself frantically. He couldn't lose Hiro, not now, not after how much work they had put into Rex and had made it through the showcase. He couldn't give up now!

Finally they were allowed to see Hiro, and Tadashi gripped his cold, tiny hand, being careful not to bother the shunt taped to the back. He held onto his brother tightly, afraid he would slip away if he loosened his grip.

Exhausted from the emotional turmoil of the day, Tadashi hadn’t even realized he’d nodded off until he was roused by Hiro shifting in the bed. His eyes fluttered open and his foggy brain slowly registered his surroundings. Then he realized that Hiro was awake and quickly rose from the chair, tightening his grip on the boy’s hand.

 “Oh thank god you‘re awake,” he breathed, hugging his brother in relief. Hiro weakly wrapped his arms around Tadashi, blinking tiredly at him as he looked around the room in confusion.

 “Why are we here?” he croaked, voice hoarse, “What happened?”

Tadashi pulled away and sighed sadly. “It’s the tumor. Luckily, it didn’t grow, but it let water into your lungs again.” He winced just thinking about the sight of his brother, looking so weak and lifeless. "You...you stopped breathing, Hiro." 

Hiro grunted, looking away guiltily he muttered, “That explains why I feel like shit.” Tadashi didn’t even bother scolding him on the cuss - they had more to worry about. Hiro coughed to clear his throat, wincing at the pain in his chest.

Tadashi frowned and reached up to run his fingers though Hiro’s hair lightly. “I’m sorry, Hiro. There _is_ some good news though,” he reached into his pocket and gave Hiro an envelope. “It came this morning.”

Hiro gasped softly, “Open it, open it! Did I get in?”

Tadashi smiled and opened the envelope cleanly before pulling out the letter. He quickly skimmed the small print it until he found the important words.

“‘We are happy to invite you, Hiro Hamada, to join us at SFIT on our full scholarship program.’” His voice rose excitedly as he continued to read, “‘We hope to see you in classes next semester.’ You did it Hiro!” He cheered and hugged Hiro carefully.

Hiro felt tears run down his face as he hugged Tadashi tightly, grinning widely because he couldn’t laugh; he could only release short wheezes and hiccups to substitute.

He couldn’t believe he really got in! He’d done what he wanted to. He was going to be able to go to college with Tadashi!

Tadashi pulled away with a bright smile before reaching up and carefully wiping Hiro’s tears, though his own eyes were glistening happily. “Good job, little bro.”

* * *

 

A few days later, Cass had gone privately to meet with a few of the doctors from the children’s cancer ward and Hiro’s doctor. When she came back, she barely managed to pull Tadashi into the hall before she burst into tears. 

"They don’t want Hiro to go to school," she sobbed heavily against his chest, "T-they think it’ll kill him…the stress and the work expected of him - they think it’ll be too much. H-Hiro’s doctor said that after running all the tests, it was the stress and anxiety from the showcase that caused him to get so sick….he said Hiro will be at higher risks of that happening again if he goes to SFIT. He also said with how much work is required, Hiro will h-have to push himself harder to meet the deadlines a-and he needs to be able to have time to rest. He shouldn’t push himself or he’ll just cause more problems."

"Oh, god..." Tadashi put a hand to his forehead, struggling to process her words.

"Oh, Tadashi…I don’t know what to tell Hiro!" she sobbed, "I don’t want to break his heart, but I also don’t want to see him suffer more…"

 “Cass…” Tadashi said, struggling to keep his voice under control, to force back the tears and sadness threatening to tear him apart. He rubbed his face wearily.“It’s… There’s nothing we can do. Whether we like it or not, we’ll have to tell him the truth. We can‘t just lead him on false hope.” He buried his face in her hair, hugging her close. “I’ll tell him if you don’t want to.” He regretted the words instantly, even though he knew it was the right thing to do.

"Please…he’ll handle it better with you there," she sniffled, "Oh, this isn’t fair!”

Tadashi felt terrible. He and Hiro had worked _so hard_ to get into SFIT. He hadn’t seen his brother so dedicated to a goal; never seen him so happy as he had been when he got the acceptance letter. Hiro hadn’t deserved any of this. He deserved to go to college and learn and create and _live_ for once. Tadashi was angry at the world, at fate, at God, at whatever the hell was making the decision to torture his brother so terribly.

He took a deep breath to gather his composure before walking into Hiro’s room. Hiro was still playing on his little handheld device. He paused the game and looked up at him, still shining ever since he’d gotten accepted into SFIT, despite how sickly he still looked. “Hey!”

Tadashi managed to force a weak smile. “Hey Hiro,” He greeted, moving to sit on the edge of Hiro’s bed, not looking forward to this.

"So, I was thinkin," Hiro croaked excitedly, breathing through the oxygen mask, "As soon as I get out we gotta…start moving my stuff to your lab. And then, you know those upgrade ideas…I had for Baymax? We could totally start on those….might have ’em done before your break, and then we can start on some of the other ideas I we had been talkin about….how’s that?"

As soon as Hiro started talking Tadashi knew he couldn’t do it. He couldn’t tell Hiro no when he looked so happy even with his lungs giving him a hard time - his eyes glowed happily and proudly, and even though he was weak he still gathered the energy to be enthusiastic about all of his ideas.

Tadashi smiled. “Sounds like a plan…”

 _We can’t give him false hope,_ he reminded himself and he sighed. “Hey, buddy…your doctor said some things, and…” Compromise, there had to be a compromise! Wait…

“And he doesn’t want you to go to SFIT - but I think you should. They’re afraid of you stressing yourself out. I think you could do online classes and come with me to lab. Online classes have no due date for SFIT, so you could do them whenever and we can still work together.” And it wasn’t like they could be in the same classes either…

Hiro’s blinked and nodded, though he looked disappointed.

“I can deal with that,” he tried to sound positive, but Tadashi’s heart ached at how sad Hiro looked. “I had wanted to actually go, but maybe this semester since I need to adjust, online classes could be okay.”

Tadashi smiled encouragingly. “Good.” He hugged Hiro lovingly. “As soon as you’re out we’ll move some of the stuff from the garage into our lab.”

Hiro smiled weakly and nodded, “Okay. Deal.”


	9. Benign

**Summary for the Chapter:**

> While the summer brings fun with friends and happiness all around, Tadashi continues working on improving Baymax's skills and the robot reveals something shocking...

It was a week and a half before Hiro was finally well enough to be let out of the hospital. It took a lot of arguing on Cass’s side to convince the doctors to let Hiro do the online schooling idea. But she was not going to take no for an answer. She was sick and tired of these doctors constantly doubting her son – er, nephew…no, screw it. Hiro and Tadashi were her boys and that was that. _No one_ was going to tell him what he could and couldn’t do and certainly not the doctor that had said on one hand that he’d be dead by now, and the other hand that they’d have a cure for him. So she was done letting them rule Hiro’s life. He would dictate his own life depending on how he felt and all she wanted those brown-nosed doctors to do was figure out a way to get the damn tumor out of her baby’s lungs. And that was that. 

Tadashi was a bit surprised as Cass told off the doctors - something he had wanted to do for a _long_  time.

They got on his nerves! Putting fear into people, piling up debt on those with either none or poor healthcare. He swore, sometimes they kept people in here on purpose instead of thinking up a solution! Hell, Baymax was now able to tell when Hiro was about to have an attack and took care of him before anything happened! On two occasions, when they forgot to deactivate him, Baymax helped seven different people by the time one doctor was available. Which the hospital didn’t like and requested the robot to remain in Hiro’s room ‘if he must stay’.

Needless to say, Hiro squeezed his Aunt as tightly as he could manage, tears running down his face and as proud and happy as could be with her. 

"I love you so much. Thank you for not giving up on me," Hiro murmured. 

"Never, babydoll, never." Cass kissed his head, "Tadashi and I will always have your back, we’ll always be your support. You can do anything you set that big brain of yours to do. You’ve proved that and more."

Tadashi smiled and nodded at Cass’ words, rubbing Hiro’s back.

During the last of the semester and through summer break, Hiro worked with Tadashi to do some upgrades with Baymax. He made it so that if anything happened and he had to go to the hospital or anything along those lines, Baymax would be wired to immediately alert Tadashi and Aunt Cass. Also, Hiro would willing subject himself to a daily examination to check on the tumor and have Baymax a second opinion if he could go out or not. Hiro didn’t want to let Tadashi or Cass know but….after that last scare of his lungs filling while he was asleep, it terrified him. It was finally starting to hit the teen about how really serious this was and he was petrified.

He tried not to let it show, though, since he knew that Tadashi loved summers, he always had. That’s why the elder teen had scheduled his classes at SFIT to match those of a normal school attendee. Well, if that attendee only had three classes a day - perks to getting core classes out of the way.

Despite that, summer was the only time he felt he had enough time to balance spending time with Hiro, spending time with their friends, helping in the café, and properly managing his side projects. In fact, this summer Hiro and he worked on Baymax quiet a bit, adding things Hiro thought up. Tadashi didn’t mind and Baymax didn’t either. The Healthcare Robot was happy both brothers were now mentally healthy and he wanted to continue to assist them.

"We should go to the park," Hiro decided one day. "Invite the others and go have a picnic. It’s so nice out."

Tadashi looked up to Hiro and smiled. “Sure!” He said in excitement. “We haven’t been to the park in a while!”

Hiro grinned, “And we haven’t seen the others in a while, so it’ll be the perfect match.”

“Right.” Tadashi agreed, moving on the couch slightly so he could get his phone out of his pants, pulling up their contacts and texting them. He knew he could just have Baymax do it, but he also knew the robot had been doing quite a bit for the brothers already.

“Baymax, go ahead and go recharge really quick so you won’t get a low battery.” He advised as he stood after the messages were sent. The robot did as he was told and Tadashi smiled to Hiro. “Let’s pack some food.”

"Alright!" Hiro cheered, excited to be getting out of the house. He stood up and followed Tadashi to the kitchen for them to start packing away a lunch for all of them. When Cass found out about their little adventure, she came and brought them some cookies from the cafe to bring along with them.

Tadashi thanked Cass and assured her they didn’t need anymore food before he gave her a hug and picked up the bag. Once Hiro and Baymax were also ready to go they left and jumped onto a trolley to ride to the park.

Hiro had to relent his strict secret keeping a little, using his crutch to walk as they headed to the park. He needed some sort of support regardless of what he wanted. Tadashi was proud of Hiro’s development, and he showed it as the three of them walked together.

When they got to the park, the gang was already waiting for them, smiling at the brothers. They all greeted each other happily.

What shocked Hiro was the fact that no one questioned the crutch. Fred had made one comment, he froze, but then it was brushed off and no explanation needed. They all just accepted it without pushing the younger to say a word. 

Honey spread out a big blanket under the shade of the tree for them all to sit on and the friends began talking about school and asking Hiro if he was excited to be going. The teen told him what his plan for the first semester was and they all agreed it would probably be best, especially with no deadlines, so Hiro could adjust to college life. They were talking about ideas and experiments and inventions and their families and just life in general. 

Hiro grinned and laughed with them. It was amazing. He felt normal, with friends and emotional support and plans for his life. He felt as if nothing was wrong with him, that he could do anything anyone else could. He felt like his life finally had some meaning to it. 

Tadashi also loved days like this - granted it happened a lot when he’d meet up with his friends and talk. However, now they were Hiro’s friends as well, and everything seemed brighter now that the most important people in his life (with the exception of Cass) were here and talking together. As they talked and snaked on the food the brothers brought Tadashi noticed the light in Hiro’s eyes.

He wished Hiro could have that light everyday.  
  


* * *

  
It was now about a month into the new semester and Tadashi was working on Baymax again. Throughout the summer the friends had met up countless times and each time they did more and more, having so much fun that it was saddening when it ended. Hiro’s stuff was moved into Tadashi’s lab and the brothers worked together a lot of the time. Cass would drop Hiro off at the labs when time came for free lab so he could go meet up with Tadashi. They’d gotten on a pretty good schedule, Hiro would do his work on the computer from home and then come meet his brother. He was just opening the door when he heard Baymax’s voice. 

“Update is complete.” Baymax’s voice sounded and Tadashi breathed a sigh. He hoped this worked. He wanted Hiro’s life to be secure…

Hiro grinned, “What new upgrade did you give him this time? Did you finally take my advice on giving him karate moves?”

Tadashi jumped slightly before turning to Hiro with a smile. “Hey Hiro, I didn’t hear you open the door - and no, I didn’t. I just updated his chip again and worked on a few of his tools and functions. I made him new tech.” He had been for a few weeks now. “I also made his database and memory bigger.” He then turned to Baymax with a smile. “Wouldn’t want him to forget how to fist bump.”

“Hiro, want to help me test him?”

"Definitely!" he chuckled, limping over to his brother and setting his backpack down and placing his crutch against the side of the table. "What do you need me to do?"

Tadashi waved Baymax to continue, the robot understood Tadashi’s plan and scanned Hiro.

“I will scan and access your personal health file.” Baymax’s stomach lit up and information flashed over his screen. “I will proceed with an X-ray of your lungs… Diagnosing your organ tissue.” Baymax droned on before astonishing news came up that shocked even Tadashi to silence. “I believe that you do not have cancer.” He said, flashing the results on his screen.

“I believe that there was an honest mistake in naming your benign tumor as cancer. This often happens in the medical field seeing as it shows the same symptoms and pattern, it usually takes years to notice as Benign doesn’t eat away tissue like cancer and is often thought to only be a ‘rare case’, or the x-ray will be taken at a time of flexasion, making it look like the tumor grew.” The screen flashed again to show all of Hiro’s x-rays, a red circle showing where the tumor never grew and the rare ones where it looked like it did. “I would recommend that this be brought up immediately to your doctors.”

Hiro’s eyes widened in shock and suddenly he couldn’t breath. He looked up to Tadashi in shock, not knowing what to do.”

Tadashi was shaken up as well before going to stand next to Hiro, putting a hand on the younger’s shoulder.

“…Elaborate on Benign, Baymax.” He requested, wanting to know more.

Baymax nodded before speaking. “Benign tumors aren’t cancerous or deadly - nor will they spread like cancer tumors. The growth is slow, if it grows at all, and is known to stop growing and even shrink. Benign tumors rarely even need to be removed if they show the signs of shrinking. Benign can be caused by many different things, but I suspect it was from inhaling smoke.

“Symptoms of benign include: persistent coughing or wheezing, shortness of breath, difficulty breathing, coughing up blood, rattling sounds in the lungs, and the threat of lung tissue collapse.

“Luckily the tumor can be removed and Hiro can be given proper treatment - which may help with his breathing and eliminate the need of crutch and shortness of breath.”

"But what doesn’t make sense to me, is my lungs occasionally fill up with fluid," Hiro looked between Baymax and Tadashi, furrowing his brows, "That  _is_ a symptom of lung cancer…”

“Yes.” Baymax agreed. “However, I believe that it happens when your lungs collapse from exhaustion and your emotional state. It has been known that mental health can often influence physical health. It could also be caused by the wrong medication.”

"I-I don’t know…" Hiro didn’t know how to wrap his head around this. He wanted to believe Baymax, he really did, but he didn’t know what was true, or right, or what. He swallowed thickly, looking up at Tadashi again, "I-I think we should call Aunt Cass and go to the hospital and get this figured out…"

Tadashi looked from Baymax to Hiro and nodded. “Y-yeah…” He looked at Baymax again. “…Can you…check again? Just to be positive.” He requested.

Baymax agreed and scanned the younger again, the same results popping up on his screen before Tadashi quickly took out his phone and called Cass, quickly explaining everything.

If Baymax was right… Then Hiro didn’t have cancer! And the tumor could be removed or shrink down in time!

Cass came as quickly as she could to pick the boys up and take them to the hospital. Needless to say, the doctors were surprised. They did several tests on Hiro to confirm what the bot had figured out and it turned out he was right. 

However, what they also found, was because had been taking the wrong medications for all this time, there were complications in his immune system and…there were cancer cells growing in his throat. 


	10. Gotta Keep Your Head Up

**Summary for the Chapter:**

> While Tadashi struggles with his anger over Hiro's misdiagnosis, Hiro grapples with his own feelings of guilt and shame after undergoing surgery.

Hiro felt like he was going to pass out between the tests they ran, which at the theory of the cancer being elsewhere prompted more tests and more blood work and more treatment options and more chaos, and the fact that Baymax said he didn’t have cancer in his lungs. He didn’t know how to wrap his head around any of this. 

Tadashi didn’t know how to feel. He was overjoyed that Hiro didn’t have lung cancer, but he was enraged that the doctors had basically  _given_  him throat cancer! They had left with more information to figure out what type of throat cancer it was but Tadashi no longer trusted them so he had Baymax dignose Hiro  _without_  those horrible tests.

It was larynx cancer and would affect Hiro’s “voice box”, but Tadashi wasn’t happy with that even if it was better then pharynx cancer. These doctors knew nothing! Years of cancer being a big problem and no one knew anything!

Now his brother was exhausted and stuck in a place he hates because of them!

"Tadashi, my sensors show that your blood pressure and heart rate have elevated," Baymax reported, "I suggest that you take deep breathes to calm yourself."

“‘Dashi,” Hiro sighed, “Don’t get angry. We’ll figure it out, just like always.”

Tadashi took a deep breath and released it shakily. “I…I can’t help it, Hiro - this isn’t fair - it isn’t right!” He insisted before rubbing his face tiredly. “You… You’ve never done anything wrong and due to your tumor being mislabeled you’ve developed real cancer…”

"Medication can’t _give_ you cancer, Tadashi," Hiro shook his head, "I bet it’s always been there; everyone just focused so much on my lungs they must have never noticed. It would explain why my throat would hurt if I raised my voice too loud. I’ve made it through this much…I can deal with a little more.

"Baymax," He looked at the robot, “I’ve been through several chemotherapy sessions, has that helped with my throat any?"

He beeped, “Yes. My scans show that due to the prior treatments, though focused on the wrong area, they did help in preventing the tumor from growing.”

Hiro motioned to the robot, looking at Tadashi, “See?”

Tadashi heaved another sigh, this time relaxing slightly as he ran a hand through his own hair. “I know, I know…but…It doesn’t change how I feel.”

"I know." Hiro sighed softly, "But, there isn’t anything we can do about it right now."

The doctors decided they were going to admit Hiro so they could get him into surgery and the Benign tumor out. They’d look into more treatment options for the new cancer, but were going to focus on this and the recovery first. They got him changed into the paper gown for it and got him started on some of the IVs and medications he’d need before the surgery. 

Tadashi was sitting next to Hiro’s bed, letting the doctors’ work despite how he felt about them. Even if Baymax could help a lot of people, the robot wasn’t very fast, and a surgery like this needed to be precise and semi-quick. In other words - he had no choice.

If he did, it wouldn’t be up to them.

Hiro was nervous and looked up at Tadashi, “W-would you come in there with me when they put me to sleep…?” he asked in a small voice, showing his fear. 

Tadashi looked to him and smiled, getting up to go to the younger Hamada before ruffling his hair lightly.

“Of course I will; I’ll be there the whole time if they let me.” He assured gently. “And I’ll definitely be here when you wake up.”

Hiro forced a weak smile. 

When they took him to the pre-surgery room, Hiro held his brother’s hand the entire time they had him breath in the anesthesia, which smelt like skittles, and they monitored his heart rate. He talked to Tadashi the whole time, until his words started slurring and he wasn’t making any sense as the medication took effect. Once he was asleep, his hand limp in Tadashi’s and the heart monitor showing his even heart rate, they took Hiro back into the surgery theater.

Tadashi put on a small smile as he talked to Hiro, helping the other take in deep breath of the anesthesia. He ran his fingers soothingly through Hiro’s hair, all the way up to Hiro passing out and the heart monitor slowing to a stead beep as he slipped into sleep. Tadashi hummed lightly to Hiro as the doctor and nurses got ready to roll Hiro away.

Tadashi reluctantly pulled his hand away and let the doctors take Hiro. He didn’t like that he couldn’t go-that was like putting this up to faith and fate was never kind to the Hamada brothers…

One of the nurses from the operation room led Tadashi out to the hall, a hand on his back and a kind look in his eye. “I’ve heard about you guys a lot, the Hamada brothers,” he said gently, “The other nurses say you’re always here with your brother. Its good for him to have that kind of support. My little sister’s in here too, so I know its rough, man. Just gotta keep hanging in there.”

As they got to the hall, the man winked, “I’ll tell you what, you promised him you’d be there when he wakes up, and I’ll make sure of it. Usually visitors aren’t supposed to be in the ICU when the patient is being watched over, but I can pull a few strings for you. I’ll get you some scrubs and you can stay with him the while time he’s being monitored right after the surgery, sound like a plan?”

Tadashi looked to the other man and at first didn’t know how to feel, but slowly a smile slipped onto his face. “Thank you! I’ll admit I was going to do it anyways, so I appreciate it.” Normally Tadashi was one for following the rules, but he made a promise to his little brother - his  _sick_  little brother. Nothing was going to stop him from keeping his promise. Especially not when he was already angry at half the staff here.

"I wouldn’t advice that," the nurse chuckled, "I did the same with my little sister and got dragged out by security. If it wasn’t for my parents, they’d have banned me from coming back in. So, I had a nursing degree, came in, badaboom," he flicked his name tag, "Now no one can tell me I can’t.”

Tadashi laughed the best he could, still not feeling good about any of this. “I doubt they would - the doctor is just about terrified of my aunt and me. Not to mention the threat of lawsuit…” he mumbled, remembering why he didn’t become a doctor like he wanted to be when he was little and Hiro was first pronounced with cancer. It turned out that if a doctor made a mistake or did something wrong they could be sued along with the hospital and, in one case, even the university they got their degree from.

Tadashi wouldn’t do that - but he’d threaten it if he had to!

"Don’t worry, though, I’ll make sure you get to stay with him. Big brothers gotta look out for their little siblings." he hummed and then went back in to go help with the surgery.

It was a fairly long wait – several hours – before the guy came back with a set of scrubs for Tadashi and led him into the ICU with Hiro. The boy was a little pale, but the heart monitor was steady and his blood oxygen levels looked better than they had been in years. His breathing under the mask was better too. He had two IVs in his hand, fluids and pain medication, and was sleeping peacefully. There were bandages wrapped tight around his chest, visible from under the hospital shirt.

"He came through great," the nurse told Tadashi, "No problems at all, his breathing improved instantly and his blood oxygen levels have been balancing out. He’s gonna be in a lot of pain on and off for the next few days from having to move his ribs a bit, but the medication will help numb it down so it won’t be so bad."

Tadashi smiled. “Thank you again,” he said before getting changed and following him into the ICU.

As soon as he saw Hiro, Tadashi’s pace picked up and he went to the other. Filling with relief once he saw that Hiro was okay and for once his chest moved up and down at a normal pace. That was good. Tadashi ran his fingers through Hiro’s hair, being extra careful due to the gloves he was wearing.

“I knew he would be okay.” Tadashi replied, affectionately as his eyes never left the younger. “My brother is a fighter.”

"He sounds like one," the man nodded with a smile.

It was an hour before they were able to move Hiro into a private room, Tadashi by his side the whole time, and it was three hours after that before he woke up. The young teen took a deeper breath through his nose to help wake himself up, groaning softly as he let it out and his eyes fluttered up. He looked up, seeing Tadashi and smiling weakly.

"Hey…" he whispered, "Made it through…one down, one to go…"

Tadashi lightly. “I told you I’d be here when you woke up.” He said affectionately, before sighing. “Get some rest. You need it.”

"Kay," he murmured and closed his eyes, "Thanks for bein’ here….You always….keep your promises….."

Tadashi smiled and ran a hand through the younger Hamada’s hair. “There’s no where else I’d rather be than with my favorite little brother.”

Hiro’s lips twitched in a weak smile, before he fell back asleep.   
  


* * *

 

  
Recovery was slow and Hiro needed Tadashi’s help with his school work, because he had trouble moving for the first week. After that, the occasional pain would come from his ribs and he’d squeeze Tadashi and Cass’s hand and whimper, gritting his teeth tightly, but it wasn’t anything unbearable, or at least nothing he hadn't already felt before.

Tadashi had reluctantly gone back to school. Luckily, he only had to go for his morning classes; Callaghan was understanding about him not wanting to leave Hiro’s side, and free lab had never been required. So he’d often come with food to eat with Hiro and Cass at lunchtime before Cass would leave to work the café. The brothers spent time, talking doing homework, helping each other, and playing videogames on emulators on Tadashi’s laptop.

It was several weeks before Hiro was allowed to come home. After nearly a month and a half of being stuck in the hospital, Hiro was ready to scream. He couldn’t stand that place! Having Tadashi, Cass, and Baymax there helped a lot, but he didn’t think Cass could possibly sign the papers faster when they finally said he could go home. He just wanted OUT!

The male nurse that he had had was really nice though, and actually seemed to know what he was doing. His name was Mateo and he told Hiro about his own sister, who was currently at home, having nearly been driven nuts staying there so long. They both laughed. Hiro decided that he liked Mateo and hoped he could be his nurse next time as well.

The doctors (and Baymax) agreed that Hiro needed to be careful and take it easy for a bit while his stitches were healing, and his chest would still be sore for at least another month. Hiro wasn’t thrilled by the idea, but anything was better then being in the hospital. The second they got home, though, Hiro swiped a chocolate filled donut from the cafe and ate half in one bite, ecstatic to finally have real food instead of the crappy hospital food. Cass didn’t even bat an eye. 

"I hate hospitals. Everyone is annoying, they’re stupid morons and don’t know what the hell they’re doing. I’m tired of dealing with them." Hiro grumbled as they went upstairs. It was clear he was not happy. 

Tadashi held back a laugh. It was funny to him because he had said those words in his own way all those weeks ago and Hiro had scolded  _him_. Oh well, Tadashi was just as glad to have Hiro back. He set to work helping Cass around the café, letting Hiro rest.

Hiro didn’t do much ‘resting’ when he got into their room. With Baymax distracted with something else, Hiro focused on studying for his classes and researching his new condition. He wanted to avoid as many attacks as he could this time around. 

His searches claimed he shouldn’t speak loudly, try to avoid diary products - which wasn’t hard; they’d been drinking soy milk for years - and to get regular treatments which consisted of taking a swab and swiping medication over the tumor in his throat. 

Hiro sighed heavily and turned off his computer, unsatisfied with his results. At least he could do _something_ to make things easier on Tadashi and Cass.  
Truthfully, Hiro wasn’t that upset about being diagnosed with something different. He'd been diagnosed with cancer at such a young age, he could barely remember life without the constant limitations. His main concern was his family. They’d been struggling so much because of him. Hiro knew that if the cafe wasn’t as popular as it was, Cass would never be able to afford the hospital bills. Along with the stress that came from worrying about his condition, Cass never seemed to get a break. And poor Tadashi, never doing anything for himself, spending every waking moment caring for or worrying about Hiro. He deserved to have a normal life, one where he could enjoy being with his friends and doing things he loved without Hiro and his condition constantly at the back of his mind.

God, why did he have to be such a burden? 

With heavy limbs, Hiro curled up on his bed, wishing the cancer would either go away or kill him already so he wouldn't cause so much trouble for his family.

**Author's Note:**

> Hope you enjoyed! Let me know what you think!


End file.
